Author/Authors :
- - نويسنده Ph.D. Candidate of Combat Desertification, Department of Watershed and Arid Zone Management, Faculty of Rangeland and Watershed, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran Akbari Morteza , - - نويسنده Professor, Department of Watershed and Arid Zone Management, Faculty of Range Land and Watershed, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran Ownegh Majid , - - نويسنده Assistant Professor, Department of Watershed and Arid Zone Management, Faculty of Range Land and Watershed, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran Asgari Hamidreza , - - نويسنده Associate Professor, Department of Watershed and Arid Zone Management, Faculty of Range Land and Watershed, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran Sadoddin Amir , - - نويسنده Assistant Professor, Department of Arid and Mountainous Regions Reclamation, Faculty of Natural Resources. University of Tehran, Tehran, Iran Khosravi Hasan
Abstract :
Based on SPI and RDI indices, changes in droughts in the semi-arid areas of west Golestan Province was assessed in the GIS environment by incorporating data from Hashemabad synoptic station and 11 climatic stations. After evaluating the ability of LARS-WG5 in the simulation period (1984-2010), downscaling of HadCM3, IPCM, and GFC models was done as a group under scenarios of A1B, A2 and B1 to evaluate changes in meteorological values of precipitation, Tmax, Tmin, and evapotranspiration during 2011-2030.Model accuracy was studied using the coefficient of determination, index of agreement (D) and the mean error. The results showed that the highest mean values of Tmax and Tmin were related to the B1 and A2scenarios, with an increasing trend of 0.81and 0.91°C, respectively. The highest mean evapotranspiration (1.34 mm) changes were under group model of B1 and A2. For precipitation, these were related to B1 (1.49 mm) and A1B (1.36 mm) scenarios. Based on the regional interpretation of drought, the central, northern and eastern parts, in spite of the current droughts, are predicted to be hit harder in the upcoming period and for more prolonged period. In this study, performance of group models to simulate climate data and use of drought indices were shown.
